/*
 * Copyright (c) 2001-2004 Caucho Technology, Inc.  All rights reserved.
 *
 * The Apache Software License, Version 1.1
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Caucho Technology (http://www.caucho.com/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "Hessian", "Resin", and "Caucho" must not be used to
 *    endorse or promote products derived from this software without prior
 *    written permission. For written permission, please contact
 *    info@caucho.com.
 *
 * 5. Products derived from this software may not be called "Resin"
 *    nor may "Resin" appear in their names without prior written
 *    permission of Caucho Technology.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL CAUCHO TECHNOLOGY OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @author Scott Ferguson
 */

package com.caucho.hessian.io;

import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

/**
 * Output stream for Hessian requests.
 * 
 * <p>
 * HessianOutput is unbuffered, so any client needs to provide its own
 * buffering.
 * 
 * <h3>Serialization</h3>
 * 
 * <pre>
 * OutputStream os = new FileOutputStream(&quot;test.xml&quot;);
 * HessianOutput out = new HessianSerializerOutput(os);
 * 
 * out.writeObject(obj);
 * os.close();
 * </pre>
 * 
 * <h3>Writing an RPC Call</h3>
 * 
 * <pre>
 * OutputStream os = ...; // from http connection
 * HessianOutput out = new HessianSerializerOutput(os);
 * String value;
 * 
 * out.startCall("hello");  // start hello call
 * out.writeString("arg1"); // write a string argument
 * out.completeCall();      // complete the call
 * </pre>
 */
public class HessianSerializerOutput extends Hessian2Output {
	/**
	 * Creates a new Hessian output stream, initialized with an underlying
	 * output stream.
	 * 
	 * @param os
	 *            the underlying output stream.
	 */
	public HessianSerializerOutput(OutputStream os) {
		super(os);
	}

	/**
	 * Creates an uninitialized Hessian output stream.
	 */
	public HessianSerializerOutput() {
		super(null);
	}

	/**
	 * Applications which override this can do custom serialization.
	 * 
	 * @param object
	 *            the object to write.
	 */
	public void writeObjectImpl(Object obj) throws IOException {
		Class cl = obj.getClass();

		try {
			Method method = cl.getMethod("writeReplace", new Class[0]);
			Object repl = method.invoke(obj, new Object[0]);

			writeObject(repl);
			return;
		} catch (Exception e) {
		}

		try {
			writeMapBegin(cl.getName());
			for (; cl != null; cl = cl.getSuperclass()) {
				Field[] fields = cl.getDeclaredFields();
				for (int i = 0; i < fields.length; i++) {
					Field field = fields[i];

					if (Modifier.isTransient(field.getModifiers()) || Modifier.isStatic(field.getModifiers()))
						continue;

					// XXX: could parameterize the handler to only deal with
					// public
					field.setAccessible(true);

					writeString(field.getName());
					writeObject(field.get(obj));
				}
			}
			writeMapEnd();
		} catch (IllegalAccessException e) {
			throw new IOExceptionWrapper(e);
		}
	}
}
